Matte finishing does not reflect light: it absorbs it. This is the difference that matters, not the aesthetics in itself. A polished surface mirrors the surrounding environment; a matte surface neutralizes it, and the piece becomes legible for its shape, not for its reflections.
The methods to achieve it are different, and they are not equivalent. Classic sandblasting—sandblasting—projects dry sand under pressure: the result is compact, with a grain perceptible even to the touch. Microblasting uses finer particles and produces a more uniform and silky surface. Glass bead-blasting replaces sand with glass microspheres: the effect is less aggressive, almost velvety. Vapor-blasting adds water to the process and delivers an even softer finish, with a slightly diffused reflection that some craftsmen call «satin matte». Micro-frosting, instead, is a chemical or mechanical abrasive applied with extreme delicacy: you find it often on precious metal dials where direct sandblasting would be too invasive.
In a well-constructed watch, matte finishing is never uniform across the entire piece. It exists for contrast. A sandblasted titanium case gains visual definition only if the chamfers—the beveled edges—are polished to a mirror finish. The matte black ceramic of the J12 Superleggera or the olive of the Captain Cook works because the bezel edge or some detail breaks the absorbing monotony. Without that contrast, matte finishing becomes flat in the worst sense of the term.
In vintage watches, matte has a precise history. The Submariner 5513 transitions to matte finishing in 1967, abandoning gilt dials: from the bench you recognize it immediately, the grain is finer than the glossy dials that would follow in 1984. The Parkerized dials of Seventies Benrus military watches use a chemical passivation process that produces an opaque blue-grey anti-reflective finish designed for field use. Today they are replicated with sandblasting on 316L: the effect is similar, the origin is not.
Matte PVD is a separate chapter: the physical vapor deposition coating is already opaque in its formulation, without needing subsequent mechanical treatment. It holds up well over time, but if it scratches, the scratch breaks the coating's continuity more noticeably than it would on bare metal.